Emmitt Smith's $2.2 million Dallas mansion and private dinner combo was snagged up faster than his 4.55-second 40-yard dash ... 'cause it sold 22 hours after it hit the market.
TMZ Sports has learned ... Smith's listing agent, Arthur Greenstein of Douglas Elliman, got 12 offers right after the 10,806-square-feet home was listed in September.
The amazing estate -- built in 1999 -- comes with five bedrooms, nine bathrooms, a dining area that sits up to 22 people, a game room and home theater.